#define SQLITE_OS_WIN

using u32 = System.UInt32;

namespace Community.CsharpSqlite
{
	public partial class Sqlite3
	{
		/*
		** 2001 September 16
		**
		** The author disclaims copyright to this source code.  In place of
		** a legal notice, here is a blessing:
		**
		**    May you do good and not evil.
		**    May you find forgiveness for yourself and forgive others.
		**    May you share freely, never taking more than you give.
		**
		******************************************************************************
		**
		** This header file (together with is companion C source-code file
		** "os.c") attempt to abstract the underlying operating system so that
		** the SQLite library will work on both POSIX and windows systems.
		**
		** This header file is #include-ed by sqliteInt.h and thus ends up
		** being included by every source file.
		*************************************************************************
		**  Included in SQLite3 port to C#-SQLite;  2008 Noah B Hart
		**  C#-SQLite is an independent reimplementation of the SQLite software library
		**
		**  SQLITE_SOURCE_ID: 2010-08-23 18:52:01 42537b60566f288167f1b5864a5435986838e3a3
		**
		*************************************************************************
		*/
#if !_SQLITE_OS_H_
		//#define _SQLITE_OS_H_

		/*
		** Figure out if we are dealing with Unix, Windows, or some other
		** operating system.  After the following block of preprocess macros,
		** all of SQLITE_OS_UNIX, SQLITE_OS_WIN, SQLITE_OS_OS2, and SQLITE_OS_OTHER
		** will defined to either 1 or 0.  One of the four will be 1.  The other
		** three will be 0.
		*/
		//#if (SQLITE_OS_OTHER)
		//# if SQLITE_OS_OTHER==1
		//#   undef SQLITE_OS_UNIX
		//#   define SQLITE_OS_UNIX 0
		//#   undef SQLITE_OS_WIN
		//#   define SQLITE_OS_WIN 0
		//#   undef SQLITE_OS_OS2
		//#   define SQLITE_OS_OS2 0
		//# else
		//#   undef SQLITE_OS_OTHER
		//# endif
		//#endif
		//#if !(SQLITE_OS_UNIX) && !SQLITE_OS_OTHER)
		//# define SQLITE_OS_OTHER 0
		//# ifndef SQLITE_OS_WIN
		//#   if defined(_WIN32) || defined(WIN32) || defined(__CYGWIN__) || defined(__MINGW32__) || defined(__BORLANDC__)
		//#     define SQLITE_OS_WIN 1
		//#     define SQLITE_OS_UNIX 0
		//#     define SQLITE_OS_OS2 0
		//#   elif defined(__EMX__) || defined(_OS2) || defined(OS2) || defined(_OS2_) || defined(__OS2__)
		//#     define SQLITE_OS_WIN 0
		//#     define SQLITE_OS_UNIX 0
		//#     define SQLITE_OS_OS2 1
		//#   else
		//#     define SQLITE_OS_WIN 0
		//#     define SQLITE_OS_UNIX 1
		//#     define SQLITE_OS_OS2 0
		//#  endif
		//# else
		//#  define SQLITE_OS_UNIX 0
		//#  define SQLITE_OS_OS2 0
		//# endif
		//#else
		//# ifndef SQLITE_OS_WIN
		//#  define SQLITE_OS_WIN 0
		//# endif
		//#endif

		private const bool SQLITE_OS_WIN = true;
		private const bool SQLITE_OS_UNIX = false;
		private const bool SQLITE_OS_OS2 = false;

		/*
		** Determine if we are dealing with WindowsCE - which has a much
		** reduced API.
		*/
		//#if (_WIN32_WCE)
		//# define SQLITE_OS_WINCE 1
		//#else
		//# define SQLITE_OS_WINCE 0
		//#endif

		/*
		** Define the maximum size of a temporary filename
		*/
#if SQLITE_OS_WIN

		//# include <windows.h>
		private const int MAX_PATH = 260;

		private const int SQLITE_TEMPNAME_SIZE = (MAX_PATH + 50); //# define SQLITE_TEMPNAME_SIZE (MAX_PATH+50)
#elif SQLITE_OS_OS2
# if FALSE //(__GNUC__ > 3 || __GNUC__ == 3 && __GNUC_MINOR__ >= 3) && OS2_HIGH_MEMORY)
//#  include <os2safe.h> /* has to be included before os2.h for linking to work */
# endif
//# define INCL_DOSDATETIME
//# define INCL_DOSFILEMGR
//# define INCL_DOSERRORS
//# define INCL_DOSMISC
//# define INCL_DOSPROCESS
//# define INCL_DOSMODULEMGR
//# define INCL_DOSSEMAPHORES
//# include <os2.h>
//# include <uconv.h>
//# define SQLITE_TEMPNAME_SIZE (CCHMAXPATHCOMP)
//#else
//# define SQLITE_TEMPNAME_SIZE 200
#endif

		/* If the SET_FULLSYNC macro is not defined above, then make it
** a no-op
*/
		//#if !SET_FULLSYNC
		//# define SET_FULLSYNC(x,y)
		//#endif

		/*
		** The default size of a disk sector
		*/
#if !SQLITE_DEFAULT_SECTOR_SIZE
		private const int SQLITE_DEFAULT_SECTOR_SIZE = 512;//# define SQLITE_DEFAULT_SECTOR_SIZE 512
#endif

		/*
** Temporary files are named starting with this prefix followed by 16 random
** alphanumeric characters, and no file extension. They are stored in the
** OS's standard temporary file directory, and are deleted prior to exit.
** If sqlite is being embedded in another program, you may wish to change the
** prefix to reflect your program's name, so that if your program exits
** prematurely, old temporary files can be easily identified. This can be done
** using -DSQLITE_TEMP_FILE_PREFIX=myprefix_ on the compiler command line.
**
** 2006-10-31:  The default prefix used to be "sqlite_".  But then
** Mcafee started using SQLite in their anti-virus product and it
** started putting files with the "sqlite" name in the c:/temp folder.
** This annoyed many windows users.  Those users would then do a
** Google search for "sqlite", find the telephone numbers of the
** developers and call to wake them up at night and complain.
** For this reason, the default name prefix is changed to be "sqlite"
** spelled backwards.  So the temp files are still identified, but
** anybody smart enough to figure out the code is also likely smart
** enough to know that calling the developer will not help get rid
** of the file.
*/
#if !SQLITE_TEMP_FILE_PREFIX
		private const string SQLITE_TEMP_FILE_PREFIX = "etilqs_"; //# define SQLITE_TEMP_FILE_PREFIX "etilqs_"
#endif

		/*
** The following values may be passed as the second argument to
** sqlite3OsLock(). The various locks exhibit the following semantics:
**
** SHARED:    Any number of processes may hold a SHARED lock simultaneously.
** RESERVED:  A single process may hold a RESERVED lock on a file at
**            any time. Other processes may hold and obtain new SHARED locks.
** PENDING:   A single process may hold a PENDING lock on a file at
**            any one time. Existing SHARED locks may persist, but no new
**            SHARED locks may be obtained by other processes.
** EXCLUSIVE: An EXCLUSIVE lock precludes all other locks.
**
** PENDING_LOCK may not be passed directly to sqlite3OsLock(). Instead, a
** process that requests an EXCLUSIVE lock may actually obtain a PENDING
** lock. This can be upgraded to an EXCLUSIVE lock by a subsequent call to
** sqlite3OsLock().
*/
		private const int NO_LOCK = 0;
		private const int SHARED_LOCK = 1;
		private const int RESERVED_LOCK = 2;
		private const int PENDING_LOCK = 3;
		private const int EXCLUSIVE_LOCK = 4;

		/*
		** File Locking Notes:  (Mostly about windows but also some info for Unix)
		**
		** We cannot use LockFileEx() or UnlockFileEx() on Win95/98/ME because
		** those functions are not available.  So we use only LockFile() and
		** UnlockFile().
		**
		** LockFile() prevents not just writing but also reading by other processes.
		** A SHARED_LOCK is obtained by locking a single randomly-chosen
		** byte out of a specific range of bytes. The lock byte is obtained at
		** random so two separate readers can probably access the file at the
		** same time, unless they are unlucky and choose the same lock byte.
		** An EXCLUSIVE_LOCK is obtained by locking all bytes in the range.
		** There can only be one writer.  A RESERVED_LOCK is obtained by locking
		** a single byte of the file that is designated as the reserved lock byte.
		** A PENDING_LOCK is obtained by locking a designated byte different from
		** the RESERVED_LOCK byte.
		**
		** On WinNT/2K/XP systems, LockFileEx() and UnlockFileEx() are available,
		** which means we can use reader/writer locks.  When reader/writer locks
		** are used, the lock is placed on the same range of bytes that is used
		** for probabilistic locking in Win95/98/ME.  Hence, the locking scheme
		** will support two or more Win95 readers or two or more WinNT readers.
		** But a single Win95 reader will lock out all WinNT readers and a single
		** WinNT reader will lock out all other Win95 readers.
		**
		** The following #defines specify the range of bytes used for locking.
		** SHARED_SIZE is the number of bytes available in the pool from which
		** a random byte is selected for a shared lock.  The pool of bytes for
		** shared locks begins at SHARED_FIRST.
		**
		** The same locking strategy and
		** byte ranges are used for Unix.  This leaves open the possiblity of having
		** clients on win95, winNT, and unix all talking to the same shared file
		** and all locking correctly.  To do so would require that samba (or whatever
		** tool is being used for file sharing) implements locks correctly between
		** windows and unix.  I'm guessing that isn't likely to happen, but by
		** using the same locking range we are at least open to the possibility.
		**
		** Locking in windows is manditory.  For this reason, we cannot store
		** actual data in the bytes used for locking.  The pager never allocates
		** the pages involved in locking therefore.  SHARED_SIZE is selected so
		** that all locks will fit on a single page even at the minimum page size.
		** PENDING_BYTE defines the beginning of the locks.  By default PENDING_BYTE
		** is set high so that we don't have to allocate an unused page except
		** for very large databases.  But one should test the page skipping logic
		** by setting PENDING_BYTE low and running the entire regression suite.
		**
		** Changing the value of PENDING_BYTE results in a subtly incompatible
		** file format.  Depending on how it is changed, you might not notice
		** the incompatibility right away, even running a full regression test.
		** The default location of PENDING_BYTE is the first byte past the
		** 1GB boundary.
		**
		*/
#if SQLITE_OMIT_WSD
//# define PENDING_BYTE     (0x40000000)
    static int PENDING_BYTE = 0x40000000;
#else

		//# define PENDING_BYTE      sqlite3PendingByte
		private static int PENDING_BYTE = 0x40000000;

#endif

		private static int RESERVED_BYTE = (PENDING_BYTE + 1);
		private static int SHARED_FIRST = (PENDING_BYTE + 2);
		private static int SHARED_SIZE = 510;

		/*
		** Wrapper around OS specific sqlite3_os_init() function.
		*/
		//int sqlite3OsInit(void);

		/*
		** Functions for accessing sqlite3_file methods
		*/

		//int sqlite3OsClose(sqlite3_file);
		//int sqlite3OsRead(sqlite3_file*, void*, int amt, i64 offset);
		//int sqlite3OsWrite(sqlite3_file*, const void*, int amt, i64 offset);
		//int sqlite3OsTruncate(sqlite3_file*, i64 size);
		//int sqlite3OsSync(sqlite3_file*, int);
		//int sqlite3OsFileSize(sqlite3_file*, i64 pSize);
		//int sqlite3OsLock(sqlite3_file*, int);
		//int sqlite3OsUnlock(sqlite3_file*, int);
		//int sqlite3OsCheckReservedLock(sqlite3_file *id, int pResOut);
		//int sqlite3OsFileControl(sqlite3_file*,int,void);
		//#define SQLITE_FCNTL_DB_UNCHANGED 0xca093fa0
		private const u32 SQLITE_FCNTL_DB_UNCHANGED = 0xca093fa0;

		//int sqlite3OsSectorSize(sqlite3_file *id);
		//int sqlite3OsDeviceCharacteristics(sqlite3_file *id);
		//int sqlite3OsShmMap(sqlite3_file *,int,int,int,object volatile *);
		//int sqlite3OsShmLock(sqlite3_file *id, int, int, int);
		//void sqlite3OsShmBarrier(sqlite3_file *id);
		//int sqlite3OsShmUnmap(sqlite3_file *id, int);

		/*
		** Functions for accessing sqlite3_vfs methods
		*/
		//int sqlite3OsOpen(sqlite3_vfs *, string , sqlite3_file*, int, int );
		//int sqlite3OsDelete(sqlite3_vfs *, string , int);
		//int sqlite3OsAccess(sqlite3_vfs *, string , int, int pResOut);
		//int sqlite3OsFullPathname(sqlite3_vfs *, string , int, char );
#if !SQLITE_OMIT_LOAD_EXTENSION
		//void *sqlite3OsDlOpen(sqlite3_vfs *, string );
		//void sqlite3OsDlError(sqlite3_vfs *, int, char );
		//void (*sqlite3OsDlSym(sqlite3_vfs *, object  *, string ))(void);
		//void sqlite3OsDlClose(sqlite3_vfs *, object  );
#endif
		//int sqlite3OsRandomness(sqlite3_vfs *, int, char );
		//int sqlite3OsSleep(sqlite3_vfs *, int);
		//int sqlite3OsCurrentTimeInt64(sqlite3_vfs *, sqlite3_int64);

		/*
		** Convenience functions for opening and closing files using
		** sqlite3Malloc() to obtain space for the file-handle structure.
		*/
		//int sqlite3OsOpenMalloc(sqlite3_vfs *, string , sqlite3_file **, int,int);
		//int sqlite3OsCloseFree(sqlite3_file );
#endif // * _SQLITE_OS_H_ */
	}
}